Preparation of chlorhydrins



April 18, 1933. w, COOK PREPARATION OF CHLORHYDRINS Filed Sept. 25, 1928 Patented Apr. 18, 1933- LEON w. coox, or ao'srmnn,

NEW roux, n. Y.,

NEW JERSEY, ASSIGHOBNL'O THE TEXAS A COBPOBATION OF DELAWARE ranranarro'n or cnnoamams Application filed September 25, 1928. Serial No. 308,832.

This invention relates to a method of preparing chlorhydrins and es ecially relates to a method of preparing c lorhydrins of liquid olefines. The preparation of chlorhydrins of liquid olefines presents considerable difiiculty since these hydrocarbons are so reactive that there is a strong tendency to produce side reactions and especially if any free chlorine be permitted to come into contact with the olefine to produce dichlor parafiins.

In order to avoid the formation of dichlor paraifins the hypochlorous acid solution is carefull prepared so that it will be free from ch orine and of low concentration, preferably not exceeding 0.75%. However, a very large quantity of such weak solution would be required to convert a given quantity or olefine to chlorhydrin. I have discovered that substantially complete converisaion of the olefine to chlorhydrin can be made hz pochlorous acid with agitation and after the latter has become exhausted, separating it from the liquid olefine containing dissolved reaction products and regenerating the hypochlorous acid solution to the desired strength. It may then be contacted again with the olefine, forming additional chlorhydrin, and this process may be repeated until the desired conversion is accomplished. Although any desired proportion of olefine to hypochlorous acid solution may be used, it has been found desirable to employ from 5 to 10 volumes of water solution of the acid to 1 volume of the olefine.

In carrying out the process, the hydrocarbon, for example, octylene may continuously be converted into the corresponding chlorhydrin by thoroughly a 'tating it with about five times its volume a water solution of hypochlorous acid which has been prepared by the introduction of'chlorine gas into a solution of sodium bicarbonate until the hypochlorous acid strength has reached about 0.75%. The solution is preferably kept cold by suitable refrigeration so that side reactions will not occur. After the hypochlorous acid solution has thoroughly reacted with the octylene, it may be separated theretreating the olefine with a solution of vessel to the other by means of from and regenerated by the addition of free chlorine as and sodium bicarbonate, if necessary. y repeated operation in this manner, a large yield of octylene chlorhydrin ma be obtained, substantially free from'the COMPANY, 01'

die lor compound. The process is particularly applicable to the preparation of chlorhydrins which are relatively insoluble in the hypochlorous acid solution. Such chlorhydrins of liquid olefines have a greater solubllity in the liquid olefine layer, and are not present in any material amountin the aqueous hypochlorous acid solution during its period" of regeneration, so that they have no opportumty of coming in contact with the free chlorine gas used during the separate regeneration of the hypochlorous acid solution. A.pparatus such as that illustrated, partlally in section, in the accompanying drawing may be employed in carrying out the process. I

1 and2 constitute similar vessels provided with stirrers 3 and 4, respectively, for agitating the contents thereof. The vessel 1 may suitably be used as a container for preparing the hypochlorous acid solution and is therefore provided with a manhole 5 through which solid sodium bicarbonate may be intro. duced. The inlet pipe 6 is provided for introducing water in the vessel 1 and the pipe 7 is adapted for introducing gaseous chlorine. There may also be provided outlet pipe 8 for withdrawing chlorine gas which has not been absorbed in the bicarbonate solution and this gas is preferably recirculated. Each of the vessels may be provided with vent pipes 9 and 10 respectively. The vessel 2 is also provided with an inlet pipe 11 for the introduction of the liquid olefines.

The vessels are connected at the bottom by pipes 14, 15, 16 and 17 and with so that liquid may be transferred from one pump 18. Pipes 14 and also serve for draining the vessels 1 and 2. Pipe 15 may also be provided with a look-box 19.

The hypochlorous acid solution is preferably made up in introduction of chlorine as into a solution of sodium bicarbonate. the. preparation the vessel 1 by the suitable pump 18 I ferred by having been ble in water,

of the solution in this vessel it may be transpump 18 and by the manipulation of suitable valves provided in the apparatusto vessel 2 where with agitation the liquid ilefine may be introduced through the pipe 11. After-the hypochlorous acid has become exhausted in reaction with the olefine, it may be returned to the vessel 1 by means of the pump 18 and there regenerated by the introluction of further chlorine gas. In withdrawing the exhausted hypochlorous solution from the vessel 2, the line-of demarcation between the aqueous liquid and the oil may be observed through look-box 19. The liquid olefine may thus be contacted any'desn'ed number of times with hypochlorous acid 7 solution which isregenerated while out of contact with the olefine. 7

What I claim is: 1. The process of preparing substantially water insoluble chlorhydrins of liquid olefines which comprises alternately contacting the further contacting the -regenerated solution with the olefines to produce additional chlorhydrins without the formation of substantial amounts of halogenated by-products.

4. The process of preparing octylene chlorhydrin which comprises alternately? contacting octylene with a solution containing not more than 0.75% generating the exhausted solution to about that strength while out of contact with theoctylene, until substantially-complete conversion to chlorhydrin has occurred.

In witness whereof I have-hereunto set my hand and seal this 19th day of September,

' LEON w. COOK.

olefines with a weak hyprochlorous acid solution of not more than 0.75% strength and regenerating'it to about that strength while out of contact with the liquid olefines and 'the'chlorhydrins so produced, whereby substantially complete conversion into chlorhydrins is obtained without the formation of substantial amounts of dichlor hydrocarbons.

2. The process whose chlorhydrins are substantially insoluble in water, which comprises contacting the olefines with an aqueous solution of hypochlorous' acid strength, separating the exhausted solution rous acid in the solution by supplying thereto free chlorine in the presence of substantially no olefines and chlorhydrins and then further contacting the regenerated solution with the of treating liquid olefines,

of not more than 0.75%

from the olefine ,material and the chlorhy-' drins so produced, regenerating hypochlo-' olefine material, whereby the latter is further converted to chlorhydrins without the formation of substantial halogen compounds. y

3. The process of treating liquid olefines, whose chlorhydrins are substantially insoluwhich comprises agitating one volume of the olefines with about 5-10 volumes of an aqueous solution of hypoamounts of polychlorous acid containing not in excess of 0.75% of hypochlorous acid, said solution prepared by introducing chlorine into aqueous sodium bicarbonate, separating the aqueous solution from the unreacted liquid olefines and dissolved chlorhydrins after the. solution has become exhausted by intermittentlydraining ofl an aqueous layer substantially free from olefines and chlorhydrins, regenerating the withdrawn solution by addition of free chlorine thereto while maintalnlng the solution out of contact with. the olefines and the chlorhydrins, and then hypochlorous acid and re- 

